I gave my truck to my son. I installed a cold air intake and header about 1-1/2 years ago, man this truck runs on the highway, easy 70,80,90mph and picked up 5mpg. However it don't like putting around town at idle speed, bucks and sputters. My son has been driving it for 2 months but driving along today it went to sputtering and died. he couldn't restart it for several minutes, and then it died immediately, and there is back-firing. he left it for an hour, went back, and it started right up and idled for 30-40 seconds and died again. Do you think it could have jumped time?? When I first got it 3 years ago it got a new fuel module & battery. He says its parked next to an industrial building and he cant hear if fuel pump is running when he turns on the key. Any ideas, thoughts??